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In general using malloc is faster, since calloc initializes the allocated memory to contain all zeroes. If this is what you want, however, then calloc can be used. The results can vary among different operating systems and environments, though. Memory allocation in an OS that uses floating blocks in heaps, such as Microsoft Windows and MacOS, should use the OS-native memory allocators instead. "Use malloc() almost always and calloc() almost never." The reason is that the initialization to zero that calloc() performs is usually not very helpful: - The initialization to "all-bits-zero" is not necessarily the same as initialization to "all-data-zero." C says very little about the representation of values in memory, nothing at all for floating-point or pointer values. On many machines all-bits-zero representations will in fact correspond to f.p. zeroes or null pointers, but this is not guaranteed by the language and there have been machines where the correspondence did not hold. If you get in the habit of using calloc() to initialize f.p. and pointer items, you may be heading for trouble. - Usually, one allocates a chunk of dynamic memory in order to store something in it -- and when you store something in it, you'll overwrite whatever was there before. Thus, the initialization performed by calloc() is usually not needed anyhow. There are occasional exceptions where all- bits-zero initialization is helpful, but they are unusual.

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The use of malloc and calloc is dynamic memory allocation. malloc allocates memory in bytes whereas calloc allocates memory in blocks. calloc initializes the allocated memory to zero. Both differs in number of arguments also. malloc takes only one argument and allocates the memory in bytes as given in the argument. calloc takes two arguments, number of variables to be allocated and size of each variable. Another difference is how the two functions deal with memory alignment.


Actually malloc allocates a block of size bytes from memory heap. It allows a program
to allocate memory as its needed, and in the exact amount needed . Where as calloc provides access to the C memory heap, which is available for dynamic allocation of
variable-sized block of memory.
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16y ago

Two differences: * new calls the object constructor, whearas calloc() simply initializes the memory to zero. * new is guaranteed to return memory, and throw an exception if it couldn't. calloc() returns NULL if it couldn't allocate memory, and therefore the return value needs to be checked.

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malloc(...) allocates memory blocks and returns a void pointer to the allocated space, or NULL if there is insufficient memory available.calloc(...) allocates an array in memory with elements initialized to 0 and returns a pointer to the allocated space. calloc(...) calls malloc(...) in order to use the C++ _set_new_mode function to set the new handler mode.

1. calloc(...) allocates a block of memory for an array of elements of a certain size. By default the block is initialized to 0. The total number of memory allocated will be (number_of_elements * size).malloc(...) takes in only a single argument which is the memory required in bytes. malloc(...) allocated bytes of memory and not blocks of memory like calloc(...).

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Q: Is it better to use malloc or calloc to allocate memory?
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Related questions

What if happen when you allocate memory by using malloc or calloc when the momory is not available contigiously?

malloc/calloc/realloc will return NULL


What is the operator is used to allocate the memory in c plus plus?

calloc operator,malloc operator


How can you allocate memory dynamically in c?

char* new_string; // could be any type new_string = (char*) malloc (5120); // allocate memory - typecast is necessary if (new_string == NULL) ... memory exception ... ... use the data ... free (new_string); // release memory when done


Difference beween calloc malloc and realloc?

There are two differences. First, is in the number of arguments. Malloc() takes a single argument (memory required in bytes), while calloc() needs two arguments (number of variables to allocate memory, size in bytes of a single variable). Secondly, malloc() does not initialize the memory allocated, while calloc() initializes the allocated memory to ZERO.Here are more opinions and answers from FAQ Farmers:The difference between malloc and calloc are: 1. malloc() allocates byte of memory, whereas calloc()allocates block of memory.Calloc(m, n) is essentially equivalent to p = m*malloc(n); memset(p, 0, m * n); The zero fill is all-bits-zero, and does not therefore guarantee useful null pointer values (see section 5 of this list) or floating-point zero values. Free is properly used to free the memory allocated by calloc.Malloc(s); returns a pointer for enough storage for an object of s bytes. Calloc(n,s); returns a pointer for enough contiguous storage for n objects, each of s bytes. The storage is all initialized to zeros.Simply, malloc takes a single argument and allocates bytes of memory as per the argument taken during its invocation. Where as calloc takes two aguments, they are the number of variables to be created and the capacity of each vaiable (i.e. the bytes per variable).This one is false:I think calloc can allocate and initialize memory, if the asked memory is available contiguously where as malloc can allocate even if the memory is not available contiguously but available at different locations.malloc will allocate a block of memoryrealloc will resize a block of memory// allocate a pointer to a block of memory to hold 10 intsint *intArray = malloc(10 * sizeof(int));// change intArray to hold 15 intsintArray = realloc(15 * sizeof(int));


Contiguous memory allocation program in Linux?

malloc or calloc


How do you use malloc and calloc to allocate memory for 100 integers?

int *p, *q; p = (int*) malloc (100 * sizeof (int)); q = (int*) calloc (100, sizeof (int)); Note that p is left in an uninitialised state whereas q is initialised with the value zero.


71 Which function should be used to free the memory allocated by calloc?

free() is a function used to free the memory allocated dynamically ,by both malloc and calloc functions. free(ptr): ptr is a pointer to a memory block which has already been creeated by malloc or calloc.


Calloc allocates a block of memory for an array of elements of a certain size?

No. The calloc function allocates a block of memory for a count of a specific type. The size of the type is already known to the compiler so does not need to be specified, it will automatically multiply the type's size by the count. With malloc, you have to allocate memory in bytes, therefore you need to calculate exactly how many bytes you will need for a given type and the number of elements of that type. Examples (allocate 100 integers): int* p = (int*) malloc (sizeof (int) * 100); int* q = (int*) calloc (int, 100); Note also that malloc does not initialise the memory whereas calloc does (the allocated memory is initialised with the value zero). As such, malloc is more efficient when you want to initialise the memory by copying from other memory. That is, there's no point initialising memory you're going to initialise manually, so long as you don't access that memory before it is initialised.


Difference between malloc and alloc?

alloc is used as header file while using malloc and calloc functions in C prog.The definition of malloc function is in the alloc.h file.It's stdlib.h to be more precise


What are new and delete operators in c plus plus?

New and Delete are the memory management operators in c++,like c language we use malloc() and calloc() functions to allocate memory and free() functiong to release the memory similarily we use new to allocate memory in C++ and Delete to release the allocated memory....


Which function should be used to free the memory allocated by calloc?

Use the free function to release memory that was previously allocated by malloc, calloc or realloc.


What is the difference between allocating memory through heap and malloc?

Nothing, malloc does allocate memory from the heap.